A laparoscopic colectomy involves the resection of the bowel at various locations. Depending on the location, the colectomy is called a right hemicolectomy, a left hemicolectomy, a sigmoid colectomy, or a total colectomy. A right hemicolectomy is the removal of the entirety of the ascending colon through a portion of transverse colon, and is the most common among the colectomy procedures. A critical step of a right hemicolectomy procedure is the ability to identify key anatomical landmarks and vasculature in order to transect the appropriate vessels and adhesions to enable the mobilization of the colon. A surgeon's first step of the procedure is to identify and transect the ileocolic vessels. The ileocolic vessels are taken down with the help of the patient being in the Trendelenburg body position with the right side upwardly positioned. This body position aides in moving away the omentum and small bowel. The ileocolic vessels are typically located adjacent to the duodenum and are encased within a mesentery layer that is made up of two peritoneum layers. During this step, the surgeon uses the duodenum as a structural landmark in locating the ileocolic vessels. Upon transection of the ileocolic vessels, there can be either a medial to lateral or lateral to medial dissection of the mesentery layer. This dissection is done through blunt dissection using laparoscopic tools or energy compatible devices that can cut and seal smaller vasculature and lymph nodes encased within the mesentery layer. For medial to lateral dissection movement is made anterior to the duodenum and Gerota's fascia to the root of the mesentery attached to the cecum and ileum. If a surgeon moves lateral to medial, dissection is performed at the ileocecal junction and moves medially, again ensuring to stay anterior to the duodenum and Gerota's fascia. Once the cecum and ileum are mobilized, the surgeon will move up the White Line of Toldt in order to reach the hepatic flexure of the colon. The White Line of Toldt is an avascular plane that is connected to the abdominal side wall through lateral adhesions. A surgeon typically takes down these adhesions and the White Line of Toldt using laparoscopic scissors or other laparoscopic devices compatible with energy. Upon taking down the White Line of Toldt, adhesions along the hepatic flexure are removed in order to allow the extracorporeal mobilization and transection of the bowel. Upon transection of bowel the surgeon performs an extracorporeal anastomosis, which reconnects the remaining bowel.
Since there are several procedural steps for a right hemicolectomy, it is important that surgeons have a way to learn and practice this surgical procedure. The model needs to be anatomically correct and include the key landmarks as well as vasculature involved with right hemicolectomy procedures. The model should be compatible with any variation of the procedural steps. As an example, either medial to lateral or lateral to medial dissection should be able to be performed on the model. Moreover, the model needs to simulate the tactile feedback that a surgeon observes during the procedure. As an example, when dissection through the mesentery layer is performed, the difference in the feeling going through the layers to get to large vessels should be apparent. Vessels should be able to be grasped, cut and clipped. Although there are several procedural steps, the majority of this procedure involves mobilizing the bowel through various dissection techniques; therefore, developing an accurate dissection model is crucial to the simulation. The organs in the model should be simulated to be able to be moved and maneuvered as they would be in the body. Additionally, the organs on the model should be attached to the model so that they can be moved in the correct direction as positioning of the model is placed in Trendelenberg or reverse Trendelenberg body positioning. There is a need for an anatomical model that addresses these issues.
Furthermore, surgical residents as well as practicing surgeons undergo extensive training prior to being qualified to practice surgery on human patients. The training teaches a variety of aspects of surgery, which can include training to develop a specific skill, to practice a specific surgical procedure, or to practice using certain surgical instruments. There is a need for synthetic simulated models that will facilitate the training for surgeons. Specifically, there is a need for a simulated tissue that closely resembles the response of human tissue that is being dissected. The ability to perform dissection between planes or dissection to skeletonize vasculature from surrounding anatomy is a skill that is found within surgical procedures. Particularly, if a laparoscopic procedure is performed, maneuvering of instruments to perform dissection is a skill that can be acquired, which will allow for an atraumatic procedure with minimal injury. The present invention sets forth such a simulated tissue.